Low carbon footprint aluminum casting component

ABSTRACT

The present disclosure provides a cast aluminum component prepared using an aluminum alloy composition. The aluminum alloy composition includes greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.15 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, and a balance of aluminum. Greater than or equal to about 40 wt. % of the aluminum alloy composition is derived from post-consumer aluminum scrap.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit and priority of Chinese Application No. 202111121702.1, filed Sep. 24, 2021. The entire disclosure of the above application is incorporated herein by reference.

INTRODUCTION

This section provides background information related to the present disclosure which is not necessarily prior art.

Components made of aluminum alloys have become ever more prevalent in various industries and applications, including general manufacturing, construction equipment, automotive or other transportation industries, home or industrial structures, aerospace, and the like. For example, aluminum alloys have been widely used in casting processes to produce automotive chassis components (e.g. knuckle, control arm, and road wheels), as the aluminum alloys offer many desirable properties, including high specific strength and good corrosion resistance.

Iron (Fe) is an inevitable, and often detrimental, impurity in various aluminum alloys. For example, iron may form brittle iron-rich intermetallic phases in cast aluminum components, which are detrimental to fatigue resistance, ductility and fracture toughness of cast aluminum components. In various instances, the iron-rich intermetallic phases appear as “script” morphologies and/or “plate” morphologies in three dimensions. For example, plate morphologies can appear as needle-like structures in two-dimensional metallographic sections. Such needle-like structures are often detrimental to fatigue resistance and fracture toughness in cast aluminum components. As such, iron impurities are often controlled below 0.15 wt. % of a total weight of the aluminum alloy, for example A356.2 aluminum alloys, such as used in the casting of safety-critical automotive components.

Low-iron aluminum alloys (e.g., less than 0.15 wt. % of iron), such as A356.2 aluminum alloys, are often produced using alloying elements, which are added to virgin or primary aluminum, such as produced from electrolytic reduction of alumina. The alumina may be refined from ore. Processes for forming the primary aluminum often generate about 15 tons to about 22 tons of carbon dioxide equivalent (“CO₂e”) per ton of primary aluminum produced. A carbon dioxide equivalent is a metric measure used to compare emissions from various greenhouse gases on the basis of the global-warming potential of the various greenhouse gases, for example, by converting amounts of other gases to the equivalent amount of carbon dioxide with the same global warming potential.

Increasing the usage of recycled aluminum scrap (including, for example only, aluminum beverage cans, aluminum architectural components (e.g., aluminum window frames), or other scrap aluminum materials), can reduce carbon dioxide equivalent significantly because greenhouse gas emissions associated with the pre-processing and re-melting of aluminum scrap is only about 5% of that associated with primary aluminum production. However, aluminum scrap is often contaminated with iron, containing iron contents greater than 0.2 wt. %. Accordingly, it would be beneficial to develop aluminum alloys, and methods of producing and processing thereof, that permit widespread use of recycled aluminum alloys, for example, by increasing tolerances to iron impurities (i.e., exhibiting improve fracture toughness, ductility and fatigue strength) as compared to low-iron alloys produced using primary aluminum.

SUMMARY

This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.

The present disclosure relates to low carbon footprint aluminum casting components, and to methods of forming the same using aluminum alloys having improved iron tolerances.

In various aspects, the present disclosure provides a cast aluminum component prepared using an aluminum alloy composition. The aluminum alloy composition includes greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.15 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, and a balance of aluminum. Greater than or equal to about 40 wt. % of the aluminum alloy composition may be derived from aluminum scrap.

In one aspect, the aluminum alloy composition may include greater than or equal to about 5 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.25 wt. % to less than or equal to about 0.4 wt. % of magnesium, and greater than or equal to about 0.2 wt. % to less than or equal to about 0.4 wt. % of iron.

In one aspect, the aluminum alloy composition may include greater than or equal to about 6.5 wt. % to less than or equal to about 7.5 wt. % of silicon, greater than or equal to about 0.25 wt. % to less than or equal to about 0.35 wt. % of magnesium, and greater than or equal to about 0.2 wt. % to less than or equal to about 0.25 wt. % of iron.

In one aspect, the aluminum alloy composition may include greater than 0 wt. % to less than or equal to about 0.2 wt. % of chromium, and greater than or equal to about 0.1 wt. % to less than or equal to about 0.25 wt. % of manganese.

In one aspect, the aluminum alloy composition may include greater than or equal to about 0.05 wt. % to less than or equal to about 0.20 wt. % of chromium, and greater than or equal to about 0.1 wt. % to less than or equal to about 0.25 wt. % of manganese.

In one aspect, a ratio of the combined concentration of chromium and manganese to iron may be greater than or equal to about 0.6 to less than or equal to about 1.2, and a ratio of chromium to manganese may be less than or equal to about 2.

In one aspect, the cast aluminum component may have an average grain size less than or equal to about 300 μm at locations where the dendrite arm spacing is greater than or equal to about 30 μm.

In one aspect, the cast aluminum component may have a tensile yield strength greater than or equal to about 140 MPa to less than or equal to about 270 MPa, and an elongation to fracture greater than or equal to about 7%.

In one aspect, the cast aluminum component includes a grain refiner selected from the group consisting of: vanadium diboride (VB₂), Ti(C,B), and combinations thereof. The grain refiners may be embedded within an aluminum grain interior of the cast aluminum component.

In one aspect, the aluminum alloy composition may consists essentially of: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, and a balance of aluminum.

In various aspects, the present disclosure provides a method for fabricating a cast aluminum component. The method may include forming an aluminum melt using greater than or equal to about 40 wt. % of aluminum scrap, where the aluminum scrap has an iron concentration greater than or equal to about 0.15 wt. %. The method may further include adjusting the aluminum melt to form an aluminum alloy composition that defines the cast aluminum component, where the aluminum alloy composition includes greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.15 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, and a balance of aluminum.

In one aspect, the cast aluminum component may have an average grain size less than or equal to about 300 μm at locations where the dendrite arm spacing is greater than or equal to about 30 μm.

In one aspect, the cast aluminum component may include a grain refiner selected from the group consisting of: vanadium diboride (VB₂), Ti(C,B), and combinations thereof. The grain refiners may be embedded within an aluminum grain interior of the cast aluminum component.

In one aspect, the aluminum alloy composition may have a ratio of the combined concentration of chromium and manganese to iron that is greater than or equal to about 0.6 to less than or equal to about 1.2, and a ratio of chromium to manganese that is less than or equal to about 2.

In one aspect, the aluminum alloy composition may include greater than 0 wt. % to less than or equal to about 0.2 wt. % of chromium, and greater than or equal to about 0.1 wt. % to less than or equal to about 0.25 wt. % of manganese.

In one aspect, the method may further include casting the aluminum alloy composition to form a cast aluminum component precursor, heat treating the cast aluminum component precursor, and aging the cooled cast aluminum component precursor to form the cast aluminum component. The aluminum alloy composition may be cast to form the cast aluminum component precursor using a casting method selected from the group consisting of: gravity casting, low pressure die casting, semi-solid die casting, and counter pressure casting, and combinations thereof. The heat treating may include heating the cast aluminum component precursor to a first temperature greater than or equal to about 450° C. to less than or equal to about 550° C. to form a heated cast aluminum component precursor, maintaining the heated cast aluminum component precursor at the first temperature for greater than or equal to about 30 minutes to less than or equal to about 12 hours, and cooling the heated cast aluminum component precursor to a second temperature less than or equal to about 120° C. to form a cooled cast aluminum component precursor. The aging may include heating the cooled cast aluminum component precursor to a third temperature greater than or equal to about 120° C. to less than or equal to about 250° C. to form a reheated cast aluminum component precursor, and maintaining the reheated cast aluminum component precursor at the third temperature for a time greater than or equal to about 30 minutes to less than or equal to about 20 hours.

In various aspects, the present disclosure provides a method for fabricating a cast aluminum component. The method may include preparing an aluminum melt that forms the cast aluminum component. The aluminum melt may include greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.15 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, and a balance of aluminum.

In one aspect, the method may further include casting the aluminum melt to form the cast aluminum component. The cast aluminum component may have an average grain size less than or equal to about 300 μm at locations where the dendrite arm spacing is greater than or equal to about 30 μm.

In one aspect, the method may further include heat treating the cast aluminum component. The heat treating may include heating the cast aluminum component to a first temperature greater than or equal to about 450° C. to less than or equal to about 550° C. to form a heated cast aluminum component, maintaining the heated cast aluminum component at the first temperature for greater than or equal to about 30 minutes to less than or equal to about 12 hours, and cooling the heated cast aluminum component to a second temperature less than or equal to about 120° C.

In one aspect, the method may further include aging the cast aluminum component. The aging may include heating the cast aluminum component to a temperature greater than or equal to about 120° C. to less than or equal to about 250° C., and maintaining the third temperature for a time greater than or equal to about 30 minutes to less than or equal to about 20 hours.

In one aspect, the aluminum melt may have a ratio of the combined concentration of chromium and manganese to iron that is greater than or equal to about 0.6 to less than or equal to about 1.2, and a ratio of chromium to manganese that is less than or equal to about 2.

In various aspects, the present disclosure provides an aluminum alloy composition that includes greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, and a balance of aluminum.

In one aspect, the aluminum alloy composition may include greater than or equal to about 5 wt. % to less than or equal to about 9 wt. % of silicon.

In one aspect, the aluminum alloy composition may include greater than or equal to about 6.5 wt. % to less than or equal to about 7.5 wt. % of silicon.

In one aspect, the aluminum alloy composition may include greater than or equal to about 0.25 wt. % to less than or equal to about 0.4 wt. % of magnesium.

In one aspect, the aluminum alloy composition may include greater than or equal to about 0.25 wt. % to less than or equal to about 0.35 wt. % of magnesium.

In one aspect, the aluminum alloy composition may include greater than or equal to about 0.2 wt. % to less than or equal to about 0.4 wt. % of iron.

In one aspect, the aluminum alloy composition may include greater than or equal to about 0.2 wt. % to less than or equal to about 0.25 wt. % of iron.

In one aspect, the aluminum alloy composition may include less than or equal to about 0.2 wt. % of chromium.

In one aspect, the aluminum alloy composition may include greater than or equal to about 0.05 wt. % to less than or equal to about 0.20 wt. % of chromium.

In one aspect, the aluminum alloy composition may include greater than or equal to about 0.1 wt. % to less than or equal to about 0.25 wt. % of manganese.

In one aspect, the aluminum alloy composition may include a ratio of the combined concentration of chromium and manganese to iron that is greater than or equal to about 0.6 to less than or equal to about 1.2.

In one aspect, the aluminum alloy composition may include a ratio of chromium to manganese that is less than or equal to about 2.

In one aspect, greater than or equal to about 40 wt. % of the aluminum alloy composition may be derived from post-consumer aluminum scrap.

In various aspects, the present disclosure provides an aluminum alloy composition that includes greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.05 wt. % to less than or equal to about 0.20 wt. % of chromium, greater than or equal to about 0.1 wt. % to less than or equal to about 0.55 wt. % of manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, and a balance of aluminum.

In one aspect, greater than or equal to about 40 wt. % of the aluminum alloy composition may be derived from post-consumer aluminum scrap.

In one aspect, the aluminum alloy composition may include greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese.

In one aspect, the aluminum alloy composition may include greater than or equal to about 5 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.25 wt. % to less than or equal to about 0.55 wt. % of magnesium; and greater than or equal to about 0.2 wt. % to less than or equal to about 0.4 wt. % of iron.

In one aspect, the aluminum alloy composition may include greater than or equal to about 6.5 wt. % to less than or equal to about 7.5 wt. % of silicon, greater than or equal to about 0.25 wt. % to less than or equal to about 0.35 wt. % of magnesium, and greater than or equal to about 0.2 wt. % to less than or equal to about 0.25 wt. % of iron.

In one aspect, a ratio of the combined concentration of chromium and manganese and to iron may be greater than or equal to about 0.6 to less than or equal to about 1.2, and a ratio of chromium to manganese may be less than or equal to about 2.

In various aspects, the present disclosure provides an aluminum alloy composition consisting essentially of: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, less than or equal to about 0.5 wt. % of cumulative impurities, and a balance of aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition that consists of: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, less than or equal to about 0.5 wt. % of cumulative impurities, and a balance of aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition consisting essentially of: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.05 wt. % to less than or equal to about 0.20 wt. % of chromium, greater than or equal to about 0.1 wt. % to less than or equal to about 0.55 wt. % of manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, less than or equal to about 0.5 wt. % of cumulative impurities, and a balance of aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition that consists of: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.05 wt. % to less than or equal to about 0.20 wt. % of chromium, greater than or equal to about 0.1 wt. % to less than or equal to about 0.55 wt. % of manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, less than or equal to about 0.5 wt. % of cumulative impurities, and a balance of aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition that consisting essentially of: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.05 wt. % to less than or equal to about 0.20 wt. % of chromium, greater than or equal to about 0.1 wt. % to less than or equal to about 0.55 wt. % of manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, and a balance of aluminum, where a combined concentration of chromium and manganese is greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. %, a ratio of the combined concentration of manganese and chromium to iron is greater than or equal to about 0.6 to less than or equal to about 1.2, less than or equal to about 0.5 wt. % of cumulative impurities, and a ratio of chromium to manganese that is less than or equal to about 2.

In various aspects, the present disclosure provides an aluminum alloy composition that consists of: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.05 wt. % to less than or equal to about 0.20 wt. % of chromium, greater than or equal to about 0.1 wt. % to less than or equal to about 0.55 wt. % of manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, and a balance of aluminum, where a combined concentration of chromium and manganese is greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. %, a ratio of the combined concentration of manganese and chromium to iron is greater than or equal to about 0.6 to less than or equal to about 1.2, and a ratio of chromium to manganese that is less than or equal to about 2.

Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

FIG. 1A is a metallographic image illustrating an example cast aluminum component including plate-morphology iron-rich intermetallic particles (circled), where the cast aluminum component was prepared using an aluminum alloy composition including about 7 wt. % of silicon, about 0.25 wt. % of iron, and substantially free of chromium;

FIG. 1B is a metallographic image illustrating an example cast aluminum component including script-shaped iron-rich intermetallic particles (circled), where the cast aluminum component was prepared using an aluminum alloy composition including about 7 wt. % of silicon, about 0.25 wt. % of iron, and about 0.2 wt. of chromium;

FIG. 2 is a graphical illustration representing a percentage of a total volume of iron-rich intermetallics in as-cast microstructure accounted for by crystallized iron-rich intermetallics, as a function of a percentage of a total volume of aluminum in the as-cast microstructure accounted for by solidified aluminum in solidification for three example aluminum alloy compositions;

FIG. 3A is a metallographic image illustrating an example cast aluminum component, where the cast aluminum component was prepared using an example aluminum alloy composition that includes about 7 wt. % of silicon, about 0.25 wt. % of iron, and about 0.2 wt. % of chromium and that is substantially free of manganese, where the example aluminum alloy composition is inoculated with vanadium diboride and the scale bar is 50 μm;

FIG. 3B is a metallographic image illustrating an example cast aluminum component, where the cast aluminum component was prepared using an example aluminum alloy composition that includes about 7 wt. % of silicon, about 0.25 wt. % of iron, about 0.12 wt. % of chromium, and 0.12 wt. % of manganese, where the example aluminum alloy composition is inoculated with vanadium diboride and the scale bar is 50 μm;

FIG. 4A is an example illustration of the coarse-grain microstructure solidification of an example cast aluminum component;

FIG. 4B is an example illustration of the fine-grained microstructure solidification of an example cast aluminum component;

FIG. 5A is an illustration of the microstructures of a A356.2 aluminum alloy that includes about 7 wt. % of silicon refined by titanium diboride;

FIG. 5B is an illustration of the microstructure of a A356.2 aluminum alloy that includes about 7 wt. % of silicon refined by vanadium diboride; and

FIG. 6 is an example illustration of an example crystallized aluminum grain.

Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.

DETAILED DESCRIPTION

Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific compositions, components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, elements, compositions, steps, integers, operations, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. Although the open-ended term “comprising,” is to be understood as a non-restrictive term used to describe and claim various embodiments set forth herein, in certain aspects, the term may alternatively be understood to instead be a more limiting and restrictive term, such as “consisting of” or “consisting essentially of.” Thus, for any given embodiment reciting compositions, materials, components, elements, features, integers, operations, and/or process steps, the present disclosure also specifically includes embodiments consisting of, or consisting essentially of, such recited compositions, materials, components, elements, features, integers, operations, and/or process steps. In the case of “consisting of,” the alternative embodiment excludes any additional compositions, materials, components, elements, features, integers, operations, and/or process steps, while in the case of “consisting essentially of,” any additional compositions, materials, components, elements, features, integers, operations, and/or process steps that materially affect the basic and novel characteristics are excluded from such an embodiment, but any compositions, materials, components, elements, features, integers, operations, and/or process steps that do not materially affect the basic and novel characteristics can be included in the embodiment.

Any method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed, unless otherwise indicated.

When a component, element, or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other component, element, or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

Although the terms first, second, third, etc. may be used herein to describe various steps, elements, components, regions, layers and/or sections, these steps, elements, components, regions, layers and/or sections should not be limited by these terms, unless otherwise indicated. These terms may be only used to distinguish one step, element, component, region, layer or section from another step, element, component, region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first step, element, component, region, layer or section discussed below could be termed a second step, element, component, region, layer or section without departing from the teachings of the example embodiments.

Spatially or temporally relative terms, such as “before,” “after,” “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially or temporally relative terms may be intended to encompass different orientations of the device or system in use or operation in addition to the orientation depicted in the figures.

Throughout this disclosure, the numerical values represent approximate measures or limits to ranges to encompass minor deviations from the given values and embodiments having about the value mentioned as well as those having exactly the value mentioned. Other than in the working examples provided at the end of the detailed description, all numerical values of parameters (e.g., of quantities or conditions) in this specification, including the appended claims, are to be understood as being modified in all instances by the term “about” whether or not “about” actually appears before the numerical value. “About” indicates that the stated numerical value allows some slight imprecision (with some approach to exactness in the value; approximately or reasonably close to the value; nearly). If the imprecision provided by “about” is not otherwise understood in the art with this ordinary meaning, then “about” as used herein indicates at least variations that may arise from ordinary methods of measuring and using such parameters. For example, “about” may comprise a variation of less than or equal to 5%, optionally less than or equal to 4%, optionally less than or equal to 3%, optionally less than or equal to 2%, optionally less than or equal to 1%, optionally less than or equal to 0.5%, and in certain aspects, optionally less than or equal to 0.1%.

In addition, disclosure of ranges includes disclosure of all values and further divided ranges within the entire range, including endpoints and sub-ranges given for the ranges.

Example embodiments will now be described more fully with reference to the accompanying drawings.

The present disclosure provides aluminum alloy compositions prepared using aluminum scraps (e.g., post-consumer aluminum scrap) including higher amounts of iron (e.g., greater than or equal to about 0.15 wt. %) and cast aluminum components including the same and having improved mechanical properties (e.g., fatigue strength, ductility, and fracture toughness). The present aluminum alloy compositions can be prepared and processed with low carbon footprints (e.g., reduction of about 50%) and at reduced costs (e.g., about 50 to about 100 per ton), as compared to aluminum alloy compositions prepared using larger amounts, or principally from, primary aluminum (such as, A356.2 aluminum alloy).

Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include, silicon (Si), magnesium (Mg), iron (Fe), manganese (Mn), chromium (Cr), titanium (Ti), and/or vanadium (V) and a balance of aluminum (Al). The aluminum alloy compositions may further include certain impurities. The impurities may include copper and/or zinc.

Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include, silicon, magnesium, iron, manganese, chromium, copper, zinc, titanium, and/or vanadium and a balance of aluminum.

Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may consist essentially of: silicon, magnesium, iron, manganese, chromium, titanium, vanadium, impurities, and aluminum. The impurities may include copper and/or zinc.

Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may consist essentially of: silicon, magnesium, iron, manganese, chromium, titanium, vanadium, copper, zinc, and aluminum.

Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may consist of: silicon, magnesium, iron, manganese, chromium, titanium, vanadium, impurities, and aluminum. The impurities may include copper and/or zinc.

Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may consist of: silicon, magnesium, iron, manganese, chromium, titanium, vanadium, copper, zinc, and aluminum.

Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may consist of: silicon, magnesium, iron, manganese, chromium, copper, zinc, titanium, vanadium, impurities, and aluminum. The impurities may include copper and/or zinc.

Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may consist of: silicon, magnesium, iron, manganese, chromium, copper, zinc, titanium, vanadium, copper, zinc, and aluminum.

In various aspects, silicon improves the castability of the aluminum alloy compositions. However, in certain variations, high amounts of silicon may negatively impact ductility, fracture toughness and fatigue resistance of cast aluminum components prepared using the aluminum alloy composition. In various aspects, the aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include greater than or equal to about 3 wt. % to less than or equal to about 9 wt. %, optionally greater than or equal to about 5 wt. % to less than or equal to about 9 wt. %, optionally greater than or equal to about 6 wt. % to less than or equal to about 8 wt. %, and in certain aspects, optionally greater than or equal to about 6.5 wt. % to less than or equal to about 7.5 wt. %, of silicon. Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include greater than or equal to 3 wt. % to less than or equal to 9 wt. %, optionally greater than or equal to 5 wt. % to less than or equal to 9 wt. %, optionally greater than or equal to 6 wt. % to less than or equal to 8 wt. %, and in certain aspects, optionally greater than or equal to 6.5 wt. % to less than or equal to 7.5 wt. %, of silicon.

For example, the aluminum alloy compositions may include greater than or equal to about 3 wt. %, optionally greater than or equal to about 3.5 wt. %, optionally greater than or equal to about 4 wt. %, optionally greater than or equal to about 4.5 wt. %, optionally greater than or equal to about 5 wt. %, optionally greater than or equal to about 5.5 wt. %, optionally greater than or equal to about 6 wt. %, optionally greater than or equal to about 6.5 wt. %, optionally greater than or equal to about 7 wt. %, optionally greater than or equal to about 7.5 wt. %, optionally greater than or equal to about 8 wt. %, and in certain aspects, optionally greater than or equal to about 8.5 wt. %, of silicon. The aluminum alloy compositions may include less than or equal to about 9 wt. %, optionally less than or equal to about 8.5 wt. %, optionally less than or equal to about 8 wt. %, optionally less than or equal to about 7.5 wt. %, optionally less than or equal to about 7 wt. %, optionally less than or equal to about 6.5 wt. %, optionally less than or equal to about 6 wt. %, optionally less than or equal to about 5.5 wt. %, optionally less than or equal to about 5 wt. %, optionally less than or equal to about 4.5 wt. %, optionally less than or equal to about 4 wt. %, and in certain aspects, optionally less than or equal to about 3.5 wt. %, of silicon. The aluminum alloy compositions may include about 3 wt. %, optionally about 3.5 wt. %, optionally about 4 wt. %, optionally about 4.5 wt. %, optionally about 5 wt. %, optionally about 5.5 wt. %, optionally about 6 wt. %, optionally about 6.5 wt. %, optionally about 7 wt. %, optionally about 7.5 wt. %, optionally about 8 wt. %, optionally about 8.5 wt. %, and in certain aspects, optionally about 9 wt. %, of silicon.

Magnesium may improve the strength of the aluminum alloy composition, for example, by allowing for the precipitation of magnesium-silicon nanoparticles during subsequent heat treatments. The volume of such magnesium-silicon nanoparticles will not increase, however, when the amount of magnesium exceeds 0.6 wt. %. In various aspects, aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. %, optionally greater than or equal to about 0.25 wt. % to less than or equal to about 0.55 wt. %, optionally greater than or equal to about 0.25 wt. % to less than or equal to about 0.4 wt. %, optionally greater than or equal to about 0.25 wt. % to less than or equal to about 0.35 wt. %, and in certain aspects, optionally greater than or equal to about 0.3 wt. % to less than or equal to about 0.35 wt. %, of magnesium. Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include greater than or equal to 0.2 wt. % to less than or equal to 0.6 wt. %, optionally greater than or equal to 0.25 wt. % to less than or equal to 0.55 wt. %, optionally greater than or equal to 0.25 wt. % to less than or equal to 0.4 wt. %, optionally greater than or equal to 0.25 wt. % to less than or equal to 0.35 wt. %, and in certain aspects, optionally greater than or equal to 0.3 wt. % to less than or equal to 0.35 wt. %, of magnesium.

For example, the aluminum alloy compositions may include greater than or equal to about 0.2 wt. %, optionally greater than or equal to about 0.25 wt. %, optionally greater than or equal to about 0.3 wt. %, optionally greater than or equal to about 0.35 wt. %, optionally greater than or equal to about 0.4 wt. %, optionally greater than or equal to about 0.45 wt. %, optionally greater than or equal to about 0.5 wt. %, and in certain aspects, optionally greater than or equal to about 0.55 wt. %, of magnesium. The aluminum alloy compositions may include less than or equal to about 0.6 wt. %, optionally less than or equal to about 0.55 wt. %, optionally less than or equal to about 0.5 wt. %, optionally less than or equal to about 0.45 wt. %, optionally less than or equal to about 0.4 wt. %, optionally less than or equal to about 0.35 wt. %, optionally less than or equal to about 0.3 wt. %, and in certain aspects, optionally less than or equal to about 0.25 wt. %, of magnesium. The aluminum alloy compositions may include about 0.2 wt. %, optionally about 0.25 wt. %, optionally about 0.3 wt. %, optionally about 0.35 wt. %, optionally about 0.4 wt. %, optionally about 0.45 wt. %, optionally about 0.5 wt. %, optionally about 0.55 wt. %, and in certain aspects, optionally about 0.6 wt. %, of magnesium.

As discussed above, iron often appears in aluminum alloy compositions as an unavoidable impurity. Iron is insoluble in solid aluminum, and instead, interacts with silicon and aluminum to form iron-rich intermetallic phases during solidification. For example, observed iron-rich intermetallic phases in cast aluminum components often include Al₅FeSi and are commonly referred to as β-phase. β-phase have, for example, undesirable three-dimensional thin-platelet morphologies, which can act as crack initiators and provide preferred crack paths, lowering toughness, ductility, and fatigue resistance of cast aluminum components. To mitigate negative effects of the β-phase, the amount of iron is often restricted, such that aluminum alloy compositions include less than or equal to about 0.12 wt. % of iron. Such low iron content aluminum alloy compositions, however, are commonly prepared using primary aluminum, which includes designated elements. For example, A356.2 aluminum alloy includes less than or equal to about 0.12 wt. % of iron, about 7 wt. % of silicon, and about 0.3 wt. % of magnesium.

To decrease costs, and reduce the carbon footprint, associated with using primary aluminum prepared, for example, using electrolytic reduction process, select aluminum scrap can be used to replace at least a portion (e.g., about 50%) of the primary aluminum. Aluminum scrap includes production aluminum scrap, as well as post-consumer aluminum scrap. Production aluminum scrap refers to aluminum scrap, such as trimmings and machining chips, that remain following various manufacturing processes. Post-consumer aluminum scrap refers to end-of life aluminum products (e.g., used beverage cans). Production aluminum scrap is often limited. Thus, it is desirable to effectively utilize post-consumer aluminum scrap. However, the amount of post-consumer aluminum scrap is often limited by its iron content, which is generally greater than about 0.15 wt. %, and often, greater than about 0.20 wt. %.

In various aspects, the aluminum alloy compositions in accordance with various aspects of the present disclosure includes comparatively high iron content, which enables the use of increased fractions of post-consumer aluminum scraps. Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. %, and in certain aspects, optionally greater than or equal to about 0.2 wt. % to less than or equal to about 0.4 wt. %, of iron. Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include greater than or equal to 0.2 wt. % to less than or equal to 0.8 wt. %, and in certain aspects, optionally greater than or equal to 0.2 wt. % to less than or equal to 0.4 wt. %, of iron.

For example, the aluminum alloy compositions may include greater than or equal to about 0.2 wt. %, optionally greater than or equal to about 0.25 wt. %, optionally greater than or equal to about 0.3 wt. %, optionally greater than or equal to about 0.35 wt. %, optionally greater than or equal to about 0.4 wt. %, optionally greater than or equal to about 0.45 wt. %, optionally greater than or equal to about 0.5 wt. %, optionally greater than or equal to about 0.55 wt. % optionally greater than or equal to about 0.6 wt. %, optionally greater than or equal to about 0.65 wt. %, optionally greater than or equal to about 0.7 wt. %, and in certain aspects, optionally greater than or equal to about 0.75 wt. %, of iron. The aluminum alloy compositions may include less than or equal to about 0.8 wt. %, optionally less than or equal to about 0.75 wt. %, optionally less than or equal to about 0.7 wt. %, optionally less than or equal to about 0.65 wt. %, optionally less than or equal to about 0.6 wt. %, optionally less than or equal to about 0.55 wt. %, optionally less than or equal to about 0.5 wt. %, optionally less than or equal to about 0.45 wt. %, optionally less than or equal to about 0.4 wt. %, optionally less than or equal to about 0.35 wt. %, optionally less than or equal to about 0.3 wt. %, and in certain aspects, optionally less than or equal to about 0.25 wt. %, of iron. The aluminum alloy compositions may include about 0.2 wt. %, optionally about 0.25 wt. %, optionally about 0.3 wt. %, optionally about 0.35 wt. %, optionally about 0.4 wt. %, optionally about 0.45 wt. %, optionally about 0.5 wt. %, optionally about 0.55 wt. %, optionally about 0.6 wt. %, optionally about 0.65 wt. %, optionally about 0.7 wt. %, optionally about 0.75 wt. %, and in certain aspects, optionally about 0.8 wt. %, of iron.

To mitigate the effects of iron-rich intermetallic phases in the present instances, where the aluminum alloy compositions include higher amounts of iron, the aluminum alloy composition further includes chromium. Chromium is effective in solidifying iron-rich intermetallics, such that the iron-rich intermetallics have a script-shaped morphology, for example as illustrated in FIG. 1B, as compared to a plate-shaped morphology, such as illustrated in FIG. 1A. Script-shaped morphologies often have more limited effects, or are benign with regard to fatigue resistance, ductility and fracture toughness. The cast aluminum component illustrated in FIG. 1A was prepared using an aluminum alloy composition that included about 7 wt. % of silicon and about 0.25 wt. % of iron, but substantially free of chromium. The cast aluminum component illustrated in FIG. 1B was prepared using an aluminum alloy composition that included about 7 wt. % of silicon, about 0.25 wt. % of iron, and about 0.2 wt. % of chromium. The script shaped Al(Cr, Fe)Si phase illustrated in FIG. 1B has a lower aspect ratio, and as such, a more compact particle size, as compared to the β-AlFeSi phase illustrated in FIG. 1A.

Similar to chromium, manganese may be used to mitigate the effects of iron-rich intermetallic phases. For example, like chromium, manganese is generally effective in solidifying iron-rich intermetallics, such that the iron-rich intermetallics have a script-shaped morphology. However, manganese is often less effective for morphology modification than chromium. That is, higher amounts of manganese for a given iron impurity may be needed to mitigate the effects of iron-rich intermetallic phases (i.e., plate morphologies to script morphologies) as compared to chromium. Using a combination of chromium and manganese, however, may help delay the crystallization of iron-rich intermetallic phases during solidification, thereby improving coupling effects and allowing for microstructure refinement and morphology modifications.

For example, FIG. 2 is a graphical illustration (for example, prepared using commercially available thermodynamic computational software) representing a percentage of a total volume of iron-rich intermetallics in an as-cast microstructure accounted for by crystallized iron-rich intermetallics, as a function of a percentage of the total volume of aluminum in the as-cast microstructure accounted for by solidified aluminum for three example aluminum alloy compositions. The first example aluminum alloy composition 210 serves as a baseline and includes about 7 wt. % of silicon and about 0.25 wt. % of iron. The second example aluminum alloy composition 220 includes about 7 wt. % of silicon, about 0.25 wt. % of iron, and about 0.2 wt. % of chromium. The third example aluminum alloy composition 230 includes about 7 wt. % of silicon, about 0.25 wt. % of iron, about 0.12 wt. % of chromium, and about 0.12 wt. % of manganese. The x-axis 200 represents the percentage (e.g., 0.4 represents 40%) of a total volume of aluminum in as-cast microstructures accounted for by the aluminum crystallized in solidification. The y-axis 202 represents percentage (e.g., 0.4 represents 40% mole fraction) of a total volume of iron-rich intermetallics in the as-cast microstructures accounted for by iron-rich intermetallics crystallized in solidification.

As discussed above, the iron-rich intermetallic phase is β-AlFeSi phase, plate morphology for the first example aluminum alloy composition 210. As illustrated in FIG. 2 , the β-AlFeSi phase for the first example aluminum alloy composition 210 does not formed until the percentage of the solidified aluminum reaches about 0.45 (i.e., 45%). When the percentage of the solidified aluminum is about 0.5 (i.e., 50%), the percentage of β-AlFeSi phase is about 0.15 (i.e., 15%). As further detailed below, in certain variations, one or more grain refiners may be further included in the first example aluminum alloy composition 210 so as to reduce the size of the solidified aluminum grains, thereby restricting, or limiting, the dispersion of the β-AlFeSi phase in the liquid channels. The solidification timing illustrated in FIG. 2 for the first example aluminum alloy composition 210 may be particularly beneficial for the use of grain refiners, such as detailed below.

As discussed above, the iron-rich intermetallic phase is Al(Cr, Fe)Si phase, script morphology for the second example aluminum alloy composition 220. As illustrated in FIG. 2 , the Al(Cr, Fe)Si phase for the second example aluminum alloy composition 220 starts to form near the beginning of solidification, and when the percentage of solidified aluminum is about 0.5 (i.e., 50%), the percentage of Al(Cr, Fe)Si phase reaches about 0.6 (i.e., 60%). Because the Al(Cr, Fe)Si phase for the second example aluminum alloy composition 220 tends to form when the fraction of solidified aluminum is low, the growth of the Al(Cr, Fe)Si phase cannot be easily restricted by solidified aluminum grains. As such, grain refiners, such as discussed below, may not cause a size reduction of the Al(Cr, Fe)Si phase.

As discussed above, the iron-rich intermetallic phase is Al(Cr, Mn, Fe)Si phase, script morphology for the third example aluminum alloy composition 230. As illustrated in FIG. 2 , the Al(Cr, Mn, Fe)Si phase for the third example aluminum alloy composition 230 begins forming later than the Al(Cr, Fe)Si phase for the second example aluminum alloy composition 220. For example, when the percentage of solidified aluminum is about 0.5 (i.e., 50%), the percentage of the Al(Cr, Mn, Fe)Si phase for the third example aluminum alloy composition 230 may be about 0.35 (i.e., 35%). Thus, partial replacement of chromium by manganese may help to reduce the size of the iron-rich intermetallic phase of the scrip morphology when grain refiners are applied, such as detailed below.

For example, FIG. 3A is a metallographic image (having a 50 μm scale) illustrating a first example cast aluminum component, where the first cast aluminum component was prepared using a first example aluminum alloy composition that includes about 7 wt. % of silicon, about 0.25 wt. % of iron, and about 0.2 wt. % of chromium and that is substantially free of manganese, where the first example aluminum alloy composition is inoculated with vanadium diboride. FIG. 3B is a metallographic image (having a 50 μm scale) illustrating a second example cast aluminum component, where the second cast aluminum component was prepared using a second example aluminum alloy composition that includes about 7 wt. % of silicon, about 0.25 wt. % of iron, about 0.12 wt. % of chromium, and 0.12 wt. % of manganese, where the second example aluminum alloy composition is inoculated with vanadium diboride. Both the first and second example aluminum alloys have an average fine gran size less than or equal to about 300 μm. However, in FIG. 3A, where the first aluminum alloy composition includes about 0.25 wt. % of iron and about 0.2 wt. % of chromium, a coarse Al(Cr, Fe)Si phase is identified. The coarse iron-rich intermetallic particles may form and grow without spacing restriction in the very early stage of solidification, that is when the fraction of solidified aluminum is very low. In contrast, in FIG. 3B, wherein the second aluminum alloy composition includes about 0.2 wt. % of chromium and 0.12 wt. % of manganese, a Al(Cr, Mn Fe) phase is identified, which has a reduced size as compared to the coarse Al(Cr, Fe)Si phase identified in the first example cast aluminum component.

To mitigate the effects of iron-rich intermetallic phases, the aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include a combined concentration of manganese and chromium. In various aspects, the aluminum alloy compositions may include a combined concentration of manganese and chromium that is greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. %, and in certain aspects, optionally greater than or equal to about 0.2 wt. % to less than or equal to about 0.3 wt. %. Aluminum alloy compositions in accordance with various aspects of the present disclosure may include a combined concentration of manganese and chromium that is greater than or equal to 0.15 wt. % to less than or equal to 0.6 wt. %, and in certain aspects, optionally greater than or equal to 0.2 wt. % to less than or equal to 0.3 wt. %.

For example, the aluminum alloy compositions may include greater than or equal to about 0.15 wt. %, optionally greater than or equal to about 0.2 wt. %, optionally greater than or equal to about 0.25 wt. %, optionally greater than or equal to about 0.3 wt. %, optionally greater than or equal to about 0.35 wt. %, optionally greater than or equal to about 0.4 wt. %, optionally greater than or equal to about 0.45 wt. %, optionally greater than or equal to about 0.5 wt. %, and in certain aspects, optionally greater than or equal to about 0.55 wt. %, of a combined concentration of manganese and chromium. The aluminum alloy compositions may include less than or equal to about 0.6 wt. %, optionally less than or equal to about 0.55 wt. %, optionally less than or equal to about 0.5 wt. %, optionally less than or equal to about 0.45 wt. %, optionally less than or equal to about 0.4 wt. %, optionally less than or equal to about 0.35 wt. %, optionally less than or equal to about 0.3 wt. %, optionally less than or equal to about 0.25 wt. %, and in certain aspects, optionally less than or equal to about 0.2 wt. %, of a combined concentration of manganese and chromium. The aluminum alloy compositions may include about 0.15 wt. %, optionally about 0.2 wt. %, optionally about 0.25 wt. %, optionally about 0.3 wt. %, optionally about 0.35 wt. %, optionally about 0.4 wt. %, optionally about 0.45 wt. %, optionally about 0.5 wt. %, optionally about 0.55 wt. %, optionally about 0.6 wt. %, of a combined concentration of manganese and chromium. To avoid the formation of iron-rich intermetallic phases during early stages of solidification, the aluminum alloy compositions may have a ratio of chromium to manganese that is less than or equal to about 2. Aluminum alloy compositions may have a ratio of chromium to manganese that is less than or equal to 2.

In order to transform substantially all (e.g., greater than or equal to about 90%, optionally greater than or equal to about 95%, optionally greater than or equal to about 96%, optionally greater than or equal to about 97%, optionally greater than or equal to about 98%, optionally greater than or equal to about 99%, and in certain aspects, optionally greater than or equal to about 99.5%) of the iron-rich intermetallic phase from plate morphology to script morphology, the aluminum alloy compositions, in accordance with various aspects of the present disclosure, may have ratios of the combined concentration of manganese and chromium to iron (i.e., (Cr+Mn)/Fe) that are greater than or equal to about 0.6. Meanwhile, to restrict volume fraction of iron-rich intermetallic phases, aluminum alloy compositions, in accordance with various aspects of the present disclosure, may have ratios of the combined concentration of manganese and chromium to iron (i.e., (Cr+Mn)/Fe) that are less than or equal to about 1.2. Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may have ratios of the combined concentration of manganese and chromium to iron (i.e., (Cr+Mn)/Fe) that are less than or equal to 1.2.

For example, the aluminum alloy compositions may have ratios of the combined concentration of manganese and chromium to iron (i.e., (Cr+Mn)/Fe) that are greater than or equal to about 0.6, optionally greater than or equal to about 0.65, optionally greater than or equal to about 0.7, optionally greater than or equal to about 0.75, optionally greater than or equal to about 0.8, optionally greater than or equal to about 0.85, optionally greater than or equal to about 0.9, optionally greater than or equal to about 0.95, optionally greater than or equal to about 1, optionally greater than or equal to about 1.05, optionally greater than or equal to about 1.1, and in certain aspects, optionally greater than or equal to about 1.15. The aluminum alloy compositions may have ratios of the combined concentration of manganese and chromium to iron (i.e., (Cr+Mn)/Fe) that are less than or equal to about 1.2, optionally less than or equal to about 1.15, optionally less than or equal to about 1.1, optionally less than or equal to about 1.05, optionally less than or equal to about 1, optionally less than or equal to about 0.95, optionally less than or equal to about 0.9, optionally less than or equal to about 0.85, optionally less than or equal to about 0.8, optionally less than or equal to about 0.75, optionally less than or equal to about 0.7, and in certain aspects, optionally less than or equal to about 0.65. In each instance, the ratio of the combined concentration of manganese and chromium to iron (i.e., (Cr+Mn)/Fe) may be about 0.6, optionally about 0.65, optionally about 0.7, optionally about 0.75, optionally about 0.8, optionally about 0.85, optionally about 0.9, optionally about 1, optionally about 1.05, optionally about 1.1, optionally about 1.15, and in certain aspects, optionally about 1.2.

In various aspects, the aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of chromium. Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include greater than or equal to 0.05 wt. % to less than or equal to 0.2 wt. % of chromium.

For example, the aluminum alloy compositions may include greater than or equal to about 0.05 wt. %, optionally greater than or equal to about 0.06 wt. %, optionally greater than or equal to about 0.07 wt. %, optionally greater than or equal to about 0.08 wt. %, optionally greater than or equal to about 0.09 wt. %, optionally greater than or equal to about 0.1 wt. %, optionally greater than or equal to about 0.11 wt. %, optionally greater than or equal to about 0.12 wt. %, optionally greater than or equal to about 0.13 wt. %, optionally greater than or equal to about 0.14 wt. %, optionally greater than or equal to about 0.15 wt. %, optionally greater than or equal to about 0.16 wt. %, optionally greater than or equal to about 0.17 wt. %, optionally greater than or equal to about 0.18 wt. %, and in certain aspects, optionally greater than or equal to about 0.19 wt. %, of chromium. The aluminum alloy compositions may include less than or equal to about 0.2 wt. %, optionally less than or equal to about 0.19 wt. %, optionally less than or equal to about 0.18 wt. %, optionally less than or equal to about 0.17 wt. %, optionally less than or equal to about 0.16 wt. %, optionally less than or equal to about 0.15 wt. %, optionally less than or equal to about 0.14 wt. %, optionally less than or equal to about 0.13 wt. %, optionally less than or equal to about 0.12 wt. %, optionally less than or equal to about 0.11 wt. %, optionally less than or equal to about 0.1 wt. %, optionally less than or equal to about 0.09 wt. %, optionally less than or equal to about 0.08 wt. %, optionally less than or equal to about 0.07 wt. %, and in certain aspects, optionally less than or equal to about 0.06 wt. %, of chromium. The aluminum alloy compositions may include about 0.05 wt. %, optionally about 0.06 wt. %, optionally about 0.07 wt. %, optionally about 0.08 wt. %, optionally about 0.09 wt. %, optionally about 0.1 wt. %, optionally about 0.11 wt. %, optionally about 0.12 wt. %, optionally about 0.13 wt. %, optionally about 0.14 wt. %, optionally about 0.15 wt. %, optionally about 0.16 wt. %, optionally about 0.17 wt. %, optionally about 0.18 wt. %, optionally about 0.19 wt. %, optionally about 0.20 wt. %, of chromium.

In various aspects, the aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include greater than or equal to about 0.05 wt. % to less than or equal to about 0.25 wt. %, and in certain aspects, optionally greater than or equal to about 0.1 wt. % to less than or equal to about 0.25 wt. %, of manganese. Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include greater than or equal to 0.05 wt. % to less than or equal to 0.25 wt. %, and in certain aspects, optionally greater than or equal to 0.1 wt. % to less than or equal to 0.25 wt. %, of manganese.

For example, the aluminum alloy compositions may include greater than or equal to about 0.05 wt. %, optionally greater than or equal to about 0.06 wt. %, optionally greater than or equal to about 0.07 wt. %, optionally greater than or equal to about 0.08 wt. %, optionally greater than or equal to about 0.09 wt. %, optionally greater than or equal to about 0.1 wt. %, optionally greater than or equal to about 0.11 wt. %, optionally greater than or equal to about 0.12 wt. %, optionally greater than or equal to about 0.13 wt. %, optionally greater than or equal to about 0.14 wt. %, optionally greater than or equal to about 0.15 wt. %, optionally greater than or equal to about 0.16 wt. %, optionally greater than or equal to about 0.17 wt. %, optionally greater than or equal to about 0.18 wt. %, optionally greater than or equal to about 0.19 wt. %, optionally greater than or equal to about 0.2 wt. %, optionally greater than or equal to about 0.21 wt. %, optionally greater than or equal to about 0.22 wt. %, optionally greater than or equal to about 0.23 wt. %, and in certain aspects, optionally greater than or equal to about 0.25 wt. %, of manganese. The aluminum alloy compositions may include less than or equal to about 0.25 wt. %, optionally less than or equal to about 0.24 wt. %, optionally less than or equal to about 0.23 wt. %, optionally less than or equal to about 0.22 wt. %, optionally less than or equal to about 0.21 wt. %, optionally less than or equal to about 0.2 wt. %, optionally less than or equal to about 0.19 wt. %, optionally less than or equal to about 0.18 wt. %, optionally less than or equal to about 0.17 wt. %, optionally less than or equal to about 0.16 wt. %, optionally less than or equal to about 0.15 wt. %, optionally less than or equal to about 0.14 wt. %, optionally less than or equal to about 0.13 wt. %, optionally less than or equal to about 0.12 wt. %, optionally less than or equal to about 0.11 wt. %, optionally less than or equal to about 0.1 wt. %, optionally less than or equal to about 0.09 wt. %, optionally less than or equal to about 0.08 wt. %, optionally less than or equal to about 0.07 wt. %, and in certain aspects, optionally less than or equal to about 0.06 wt. %, of manganese. The aluminum alloy compositions may include about 0.05 wt. %, optionally about 0.06 wt. %, optionally about 0.07 wt. %, optionally about 0.08 wt. %, optionally about 0.09 wt. %, optionally about 0.1 wt. %, optionally about 0.11 wt. %, optionally about 0.12 wt. %, optionally about 0.13 wt. %, optionally about 0.14 wt. %, optionally about 0.15 wt. %, optionally about 0.16 wt. %, optionally about 0.17 wt. %, optionally about 0.18 wt. %, optionally about 0.19 wt. %, optionally about 0.20 wt. %, optionally about 0.21 wt. %, optionally about 0.22 wt. %, optionally about 0.23 wt. %, optionally about 0.24 wt. %, and in certain aspects, optionally about 0.25 wt. %, of manganese.

As mentioned above, to further mitigate the effect of iron-rich intermetallic phases in the present instances, where the aluminum alloy compositions include higher amounts of iron, grain refining processes can be applied during solidification so as to further reduce the particle sizes of the iron-rich intermetallics, for example, having script-shaped morphologies, as discussed above. Smaller iron-rich intermetallics phases are often less harmful to fatigue resistance and fracture toughness. As illustrated in FIG. 4B, fine-grained microstructures 450 have smaller liquid channels 460 substantially surrounded, or enclosed by, solidified aluminum grains 462, while coarse-grain microstructures 400, as illustrated in FIG. 4A, have a large liquid channels 410 substantially surrounded, or enclosed by, solidified aluminum grains 412. During solidification, iron-rich intermetallics are formed in the liquid channels 410, 460. Reducing the size of the liquid channel 410, 460 limits the space available for growth of the iron-rich intermetallics, thereby reducing the particle sizes of the iron-rich intermetallics.

In various aspects, grain refining during aluminum casting may include inoculating an aluminum alloy melt with intermetallic particles that can serve as heterogeneous nucleation substrates for aluminum grains. In certain variations, grain refiners may include vanadium diboride (VB₂) and/or Ti(C,B), which are more potent for refining grain size than other grain refiners, such as titanium diboride (TiB₂). For example, FIG. 5A depicts the microstructures of a A356.2 aluminum alloy that includes about 7 wt. % of silicon refined by titanium diboride, while FIG. 5B depicts the microstructure of a A356.2 aluminum alloy that includes about 7 wt. % of silicon refined by vanadium diboride. As illustrated, the grain size in FIG. 5B is about less (e.g., about one-third less) than that of the grain size in FIG. 5A.

To take advantage of grain refining properties, in various aspects, the aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include a combined concentration of titanium and vanadium that is greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. %. Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include a combined concentration of titanium and vanadium that is greater than or equal to 0.05 wt. % to less than or equal to 0.2 wt. %.

For example, the aluminum alloy compositions may include greater than or equal to about 0.05 wt. %, optionally greater than or equal to about 0.1 wt. %, and in certain aspects, optionally greater than or equal to about 0.15 wt. %, of a combined concentration of titanium and vanadium. The aluminum alloy compositions may include less than or equal to about 0.2 wt. %, optionally less than or equal to about 0.15 wt. %, and in certain aspects, optionally less than or equal to about 0.1 wt. %, of a combined concentration of titanium and vanadium. The aluminum alloy compositions may include about 0.05 wt. %, optionally about 0.1 wt. %, optionally about 0.15 wt. %, and in certain aspects, optionally about 0.2 wt. %, of a combined concentration of titanium and vanadium. Vanadium diboride and/or Ti(C,B), used here as a nucleation substrate, can often be found in the aluminum grain interior.

In various aspects, grain refining during aluminum casting may include modulating cooling rates during the formation of the cast aluminum components. For example, grain size often decreases with increasing cooling rates. In certain variations, the cooling rate experienced by cast components may be qualitatively evaluated by the size of a dendrite arm spacing (“DAS”), which is reduced as cooling rates increase. For example, as illustrated in FIG. 6 , dendrite arm spacing 602 of a crystallized aluminum grain 600 may be determined by dividing a total space 610 from a first arm 612 to a last arm 614 by the number of total dendrite arms between, and including, the first arm 612 and the last arm 614. Several measurements may be collected so to provide an average dendrite arm spacing 602. Cast aluminum components including titanium diboride often have a dendrite arm spacing that is greater than or equal to about 30 μm, and the grain size of the microstructure may be greater than about 350 μm. In contrast, cast aluminum components including vanadium diboride and/or Ti(C,B) often have a dendrite arm spacing that is greater than or equal to about 30 μm, and the grain size of the microstructure may be less than or equal to about 300 μm.

In various aspects, the aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include unintentional/unavoidable impurities (e.g., copper and/or zinc). For example, the aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include less than or equal to about 0.5 wt. %, optionally less than or equal to about 0.4 wt. %, optionally less than or equal to about 0.3 wt. %, optionally less than or equal to about 0.2 wt. %, optionally less than or equal to about 0.1 wt. %, and in certain aspects, optionally less than or equal to about 0.05 wt. %, of the unintentional/unavoidable impurities, such as copper and/or zinc. Aluminum alloy compositions, in accordance with various aspects of the present disclosure, may include less than or equal to 0.5 wt. %, optionally less than or equal to 0.4 wt. %, optionally less than or equal to 0.3 wt. %, optionally less than or equal to 0.2 wt. %, optionally less than or equal to 0.1 wt. %, and in certain aspects, optionally less than or equal to 0.05 wt. %, of the unintentional/unavoidable impurities, such as copper and/or zinc.

In each instance, the aluminum alloy compositions, in accordance with various aspects of the present disclosure, include a balance of aluminum. For example, in certain variations, the aluminum alloy compositions include greater than or equal to about 85 wt. %, optionally greater than or equal to about 90 wt. %, and in certain aspects, optionally greater than or equal to about 95 wt. %, of aluminum.

In various aspects, greater than or equal to about 40 wt. %, optionally greater than or equal to about 50 wt. %, optionally greater than or equal to about 55 wt. %, optionally greater than or equal to about 60%, optionally greater than or equal to about 65%, optionally greater than or equal to about 70%, optionally greater than or equal to about 75 wt. %, optionally greater than or equal to about 80%, optionally greater than or equal to about 85%, optionally greater than or equal to about 90%, optionally greater than or equal to about 95%, optionally greater than or equal to about 96%, optionally greater than or equal to about 97%, optionally greater than or equal to about 98%, and in certain aspects, optionally greater than or equal to about 99%, of the aluminum alloy composition may be derived from post-consumer aluminum scrap (including, for example only, aluminum beverage cans, aluminum architectural components (such as, aluminum window frames), or other scrap aluminum materials), which commonly include higher levels of iron. In certain variations, greater than or equal to 40 wt. %, optionally greater than or equal to 50 wt. %, optionally greater than or equal to 55 wt. %, optionally greater than or equal to 60%, optionally greater than or equal to 65%, optionally greater than or equal to 70%, optionally greater than or equal to 75 wt. %, optionally greater than or equal to 80%, optionally greater than or equal to 85%, optionally greater than or equal to 90%, optionally greater than or equal to 95%, optionally greater than or equal to 96%, optionally greater than or equal to 97%, optionally greater than or equal to 98%, and in certain aspects, optionally greater than or equal to 99%, of the aluminum alloy composition may be derived from post-consumer aluminum scrap (including, for example only, aluminum beverage cans, aluminum architectural components (such as, aluminum window frames), or other scrap aluminum materials), which commonly include higher levels of iron.

As such, the carbon footprint associated with the production of the aluminum alloy composition, and products including the same, may be reduced by greater than or equal to about 40%, optionally greater than or equal to about 42%, optionally greater than or equal to about 44%, optionally greater than or equal to about 46%, optionally greater than or equal to about 48%, optionally greater than or equal to about 50%, optionally greater than or equal to about 52%, optionally greater than or equal to about 54%, optionally greater than or equal to about 56%, optionally greater than or equal to about 58%, optionally greater than or equal to about 60%, optionally greater than or equal to about 62%, optionally greater than or equal to about 64%, optionally greater than or equal to about 66%, optionally greater than or equal to about 68%, and in certain aspects, optionally greater than or equal to about 70%, as compared to aluminum alloys prepared using primary aluminum. The carbon footprint associated with the production of the aluminum alloy composition, and products including the same, may be reduced by greater than or equal to 40%, optionally greater than or equal to 42%, optionally greater than or equal to 44%, optionally greater than or equal to 46%, optionally greater than or equal to 48%, optionally greater than or equal to 50%, optionally greater than or equal to 52%, optionally greater than or equal to 54%, optionally greater than or equal to 56%, optionally greater than or equal to 58%, optionally greater than or equal to 60%, optionally greater than or equal to 62%, optionally greater than or equal to 64%, optionally greater than or equal to 66%, optionally greater than or equal to 68%, and in certain aspects, optionally greater than or equal to 70%, as compared to aluminum alloys prepared using primary aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition that includes greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, and a balance of aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition that includes greater than or equal to 3 wt. % to less than or equal to 9 wt. % of silicon, greater than or equal to 0.2 wt. % to less than or equal to 0.6 wt. % of magnesium, greater than or equal to 0.2 wt. % to less than or equal to 0.8 wt. % of iron, greater than or equal to 0.15 wt. % to less than or equal to 0.6 wt. % of a combined concentration of chromium and manganese, greater than or equal to 0.05 wt. % to less than or equal to 0.2 wt. % of a combined concentration of vanadium and titanium, and a balance of aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition consisting essentially of: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, cumulative impurities at less than or equal to about 0.5 wt. %, and a balance of aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition consisting essentially of: greater than or equal to 3 wt. % to less than or equal to 9 wt. % of silicon, greater than or equal to 0.2 wt. % to less than or equal to 0.6 wt. % of magnesium, greater than or equal to 0.2 wt. % to less than or equal to 0.8 wt. % of iron, greater than or equal to 0.15 wt. % to less than or equal to 0.6 wt. % of a combined concentration of chromium and manganese, greater than or equal to 0.05 wt. % to less than or equal to 0.2 wt. % of a combined concentration of vanadium and titanium, cumulative impurities at less than or equal to 0.5 wt. %, and a balance of aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition that consists of: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, impurities (e.g., cumulative impurities at less than or equal to about 0.5 wt. %), and a balance of aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition consisting essentially of: greater than or equal to 3 wt. % to less than or equal to 9 wt. % of silicon, greater than or equal to 0.2 wt. % to less than or equal to 0.6 wt. % of magnesium, greater than or equal to 0.2 wt. % to less than or equal to 0.8 wt. % of iron, greater than or equal to 0.15 wt. % to less than or equal to 0.6 wt. % of a combined concentration of chromium and manganese, greater than or equal to 0.05 wt. % to less than or equal to 0.2 wt. % of a combined concentration of vanadium and titanium, cumulative impurities at less than or equal to 0.5 wt. %, and a balance of aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition consisting essentially of: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.05 wt. % to less than or equal to about 0.20 wt. % of chromium, greater than or equal to about 0.1 wt. % to less than or equal to about 0.55 wt. % of manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, cumulative impurities at less than or equal to about 0.5 wt. %, and a balance of aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition consisting essentially of: greater than or equal to 3 wt. % to less than or equal to 9 wt. % of silicon, greater than or equal to 0.2 wt. % to less than or equal to 0.6 wt. % of magnesium, greater than or equal to 0.2 wt. % to less than or equal to 0.8 wt. % of iron, greater than or equal to 0.05 wt. % to less than or equal to 0.20 wt. % of chromium, greater than or equal to 0.1 wt. % to less than or equal to 0.55 wt. % of manganese, greater than or equal to 0.05 wt. % to less than or equal to 0.2 wt. % of a combined concentration of vanadium and titanium, cumulative impurities at less than or equal to 0.5 wt. %, and a balance of aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition that consists of: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.05 wt. % to less than or equal to about 0.20 wt. % of chromium, greater than or equal to about 0.1 wt. % to less than or equal to about 0.55 wt. % of manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, impurities, and a balance of aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition that consists of: greater than or equal to 3 wt. % to less than or equal to 9 wt. % of silicon, greater than or equal to 0.2 wt. % to less than or equal to 0.6 wt. % of magnesium, greater than or equal to 0.2 wt. % to less than or equal to 0.8 wt. % of iron, greater than or equal to 0.05 wt. % to less than or equal to 0.20 wt. % of chromium, greater than or equal to 0.1 wt. % to less than or equal to 0.55 wt. % of manganese, greater than or equal to 0.05 wt. % to less than or equal to 0.2 wt. % of a combined concentration of vanadium and titanium, impurities, and a balance of aluminum.

In various aspects, the present disclosure provides an aluminum alloy composition that consisting essentially of: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.05 wt. % to less than or equal to about 0.20 wt. % of chromium, greater than or equal to about 0.1 wt. % to less than or equal to about 0.55 wt. % of manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, cumulative impurities at less than or equal to about 0.5 wt. %, and a balance of aluminum, where a combined concentration of chromium and manganese is greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. %, a ratio of the combined concentration of manganese and chromium to iron is greater than or equal to about 0.6 to less than or equal to about 1.2, and a ratio of chromium to manganese that is less than or equal to about 2.

In various aspects, the present disclosure provides an aluminum alloy composition that consisting essentially of: greater than or equal to 3 wt. % to less than or equal to 9 wt. % of silicon, greater than or equal to 0.2 wt. % to less than or equal to 0.6 wt. % of magnesium, greater than or equal to 0.2 wt. % to less than or equal to 0.8 wt. % of iron, greater than or equal to 0.05 wt. % to less than or equal to 0.20 wt. % of chromium, greater than or equal to 0.1 wt. % to less than or equal to 0.55 wt. % of manganese, greater than or equal to 0.05 wt. % to less than or equal to 0.2 wt. % of a combined concentration of vanadium and titanium, cumulative impurities at less than or equal to 0.5 wt. %, and a balance of aluminum, where a combined concentration of chromium and manganese is greater than or equal to 0.15 wt. % to less than or equal to 0.6 wt. %, a ratio of the combined concentration of manganese and chromium to iron is greater than or equal to 0.6 to less than or equal to 1.2, and a ratio of chromium to manganese that is less than or equal to 2.

In various aspects, the present disclosure provides an aluminum alloy composition that consists of: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.05 wt. % to less than or equal to about 0.20 wt. % of chromium, greater than or equal to about 0.1 wt. % to less than or equal to about 0.55 wt. % of manganese, greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium, impurities, and a balance of aluminum, where a combined concentration of chromium and manganese is greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. %, a ratio of the combined concentration of manganese and chromium to iron is greater than or equal to about 0.6 to less than or equal to about 1.2, and a ratio of chromium to manganese that is less than or equal to about 2.

In various aspects, the present disclosure provides an aluminum alloy composition that consists of: greater than or equal to 3 wt. % to less than or equal to 9 wt. % of silicon, greater than or equal to 0.2 wt. % to less than or equal to 0.6 wt. % of magnesium, greater than or equal to 0.2 wt. % to less than or equal to 0.8 wt. % of iron, greater than or equal to 0.05 wt. % to less than or equal to 0.20 wt. % of chromium, greater than or equal to 0.1 wt. % to less than or equal to 0.55 wt. % of manganese, greater than or equal to 0.05 wt. % to less than or equal to 0.2 wt. % of a combined concentration of vanadium and titanium, impurities, and a balance of aluminum, where a combined concentration of chromium and manganese is greater than or equal to 0.15 wt. % to less than or equal to 0.6 wt. %, a ratio of the combined concentration of manganese and chromium to iron is greater than or equal to 0.6 to less than or equal to 1.2, and a ratio of chromium to manganese that is less than or equal to 2.

Aluminum alloy compositions in accordance with various aspects of the present disclosure may be cast to form cast aluminum components using various casting processes, including, for example only, gravity casting, low pressure casting, semi-solid casting, counter pressure casting, and the like. In certain variations, the cast aluminum components may be, for example, vehicle components and/or architectural components. In various aspects, vehicle components may include, for example only, a road wheel, a knuckle, a control arm, a bracket, a node, a brake caliper, a subframe member, and the like. In each instance, the cast aluminum components may have a tensile yield strength greater than or equal to about 140 MPa to less than or equal to about 270 MPa (and in certain aspects, optionally greater than or equal to about 180 MPa to less than or equal to about 270 MPa), and an elongation to fracture of greater than or equal to about 7%. The skilled artisan will recognize that these and other mechanical properties may vary, in certain variations, by choice of heat treatment. The combined strength and ductility of the cast aluminum components, however, is often dependent on iron content, such as detailed above.

In various aspects, the present disclosure provides an example method for forming cast aluminum components using aluminum alloy compositions like those detailed above. The method includes, for example, preparing an aluminum alloy melt. The aluminum alloy melt may be prepared by subjecting an master alloy ingot to high temperatures. The master alloy ingot may include an aluminum alloy composition that comprises greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon, greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium, greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron, greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese, and greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium. The aluminum alloy melt may include greater or equal to about greater than or equal to about 40 wt. % of the post-consumer aluminum scrap, and less than or equal to about 25 wt. % of primary aluminum. The master alloy ingot may include an aluminum alloy composition that comprises greater than or equal to 3 wt. % to less than or equal to 9 wt. % of silicon, greater than or equal to 0.2 wt. % to less than or equal to 0.6 wt. % of magnesium, greater than or equal to 0.2 wt. % to less than or equal to 0.8 wt. % of iron, greater than or equal to 0.15 wt. % to less than or equal to 0.6 wt. % of a combined concentration of chromium and manganese, and greater than or equal to 0.05 wt. % to less than or equal to 0.2 wt. % of a combined concentration of vanadium and titanium. The aluminum alloy melt may include greater or equal to\ greater than or equal to 40 wt. % of the post-consumer aluminum scrap, and less than or equal to 25 wt. % of primary aluminum.

In various aspects, the method further includes casting the aluminum alloy melt directly to form an cast aluminum component, for example using gravity casting, low pressure die casting, semi-solid casting or counter pressure casting, or the like. In certain variations, the method includes casting the aluminum alloy melt to form an alloy ingot that is subsequently re-melted and cast to form the cast aluminum component.

In various aspects, the method further includes subjecting the cast aluminum component to one or more heat treatment processes, which can modify the effects of iron, as discussed above. The one or more heat treatment processes may be selected such that the final cast aluminum component has the selected mechanical properties. The one or more heat treatment processes may include a solution heat treatment, a quenching process, and/or an aging heat treatment. For example, in certain variations, the quenching process may follow the solution heat treatment and the aging heat treatment may follow the quenching process.

In various aspects, the solution heat treatment process may include heating (for example, using a furnace) the cast aluminum component to a temperature greater than or equal to about 450° C. to less than or equal to about 550° C., optionally greater than or equal to about 480° C. to less than or equal to about 550° C., and in certain aspects, optionally greater than or equal to about 530° C. to less than or equal to about 545° C. The solution heat treatment process may include heating (for example, using a furnace) the cast aluminum component to a temperature greater than or equal to 450° C. to less than or equal to 550° C., optionally greater than or equal to 480° C. to less than or equal to 550° C., and in certain aspects, optionally greater than or equal to 530° C. to less than or equal to 545° C.

For example, the cast aluminum component may be heated to a temperature greater than or equal to about 450° C., optionally greater than or equal to about 460° C., optionally greater than or equal to about 470° C., optionally greater than or equal to about 480° C., optionally greater than or equal to about 490° C., optionally greater than or equal to about 500° C., optionally greater than or equal to about 510° C., optionally greater than or equal to about 520° C., optionally greater than or equal to about 530° C., and in certain aspects, optionally greater than or equal to about 540° C. The cast aluminum component may be heated to a temperature less than or equal to about 550° C., optionally less than or equal to about 540° C., optionally less than or equal to about 530° C., optionally less than or equal to about 520° C., optionally less than or equal to about 510° C., optionally less than or equal to about 500° C., optionally less than or equal to about 490° C., optionally less than or equal to about 480° C., optionally less than or equal to about 470° C., and in certain aspects, optionally less than or equal to about 460° C. The cast aluminum component may be heated to about 450° C., optionally about 455° C., optionally about 460° C., optionally about 465° C., optionally about 470° C., optionally about 475° C., optionally about 480° C., optionally about 485° C., optionally about 490° C., optionally about 495° C., optionally about 500° C., optionally about 505° C., optionally about 510° C., optionally about 515° C., optionally about 520° C., optionally about 525° C., optionally about 530° C., optionally about 535° C., optionally about 540° C., optionally about 445° C., and in certain aspects, optionally about 550° C.

Such temperatures may be maintained for a time greater than or equal to about 0.5 hours to less than or equal to about 12 hours. Such temperatures may be maintained for a time greater than or equal to 0.5 hours to less than or equal to 12 hours.

For example, the temperature may be maintained for greater than or equal to about 1 hour, optionally greater than or equal to about 1.5 hour, optionally greater than or equal to about 2 hour, optionally greater than or equal to about 2.5 hour, optionally greater than or equal to about 3 hour, optionally greater than or equal to about 3.5 hour, optionally greater than or equal to about 4 hour, optionally greater than or equal to about 4.5 hour, optionally greater than or equal to about 5 hour, optionally greater than or equal to about 5.5 hour, optionally greater than or equal to about 6 hour, optionally greater than or equal to about 6.5 hour, optionally greater than or equal to about 7 hour, optionally greater than or equal to about 7.5 hour, optionally greater than or equal to about 8 hour, optionally greater than or equal to about 8.5 hour, optionally greater than or equal to about 9 hour, optionally greater than or equal to about 9.5 hour, optionally greater than or equal to about 10 hour, optionally greater than or equal to about 10.5 hour, optionally greater than or equal to about 11 hour, and in certain aspects, optionally greater than or equal to about 11.5 hour. The temperature may be maintained for less than or equal to about 12 hours, optionally less than or equal to about 11.5 hours, optionally less than or equal to about 11 hours, optionally less than or equal to about 10.5 hours, optionally less than or equal to about 10 hours, optionally less than or equal to about 9.5 hours, optionally less than or equal to about 9 hours, optionally less than or equal to about 8.5 hours, optionally less than or equal to about 8 hours, optionally less than or equal to about 7.5 hours, optionally less than or equal to about 7 hours, optionally less than or equal to about 6.5 hours, optionally less than or equal to about 6 hours, optionally less than or equal to about 5.5 hours, optionally less than or equal to about 5 hours, optionally less than or equal to about 4.5 hours, optionally less than or equal to about 4 hours, optionally less than or equal to about 3.5 hours, optionally less than or equal to about 3 hours, optionally less than or equal to about 2.5 hours, optionally less than or equal to about 2 hours, and in certain aspects, optionally less than or equal to about 1.5 hours. The temperature may be maintained for about 1 hour, optionally about 1.5 hours, optionally about 2.5 hours, optionally about 3 hours, optionally about 3.5 hours, optionally about 4 hours, optionally about 4.5 hours, optionally about 5 hours, optionally about 5.5 hours, optionally about 6 hours, optionally about 6.5 hours, optionally about 7 hours, optionally about 7.5 hours, optionally about 8 hours, optionally about 8.5 hours, optionally about 9 hours, optionally about 9.5 hours, optionally about 10 hours, optionally about 10.5 hours, optionally about 11 hours, optionally about 11.5 hours, and in certain aspects, optionally about 12 hours.

In various aspects, the quenching process occurs using liquid mist quench and/or liquid quench. In certain variations, the quenching process may be performed at a rate fast or high enough so as to avoid formation of undesirable precipitations, but also, slow or low enough so as to avoid generation of cracks or distortions. In each instance, quenching process generally includes lowering the temperature of the cast article to a temperature less than or equal to about 120° C. The quenching process may include lowering the temperature of the cast article to a temperature less than or equal to 120° C.

In various aspects, the aging process may include heating the cast aluminum component to a temperature of greater than or equal to about 120° C. to less than or equal to about 250° C., optionally greater than or equal to about 130° C. to less than or equal to about 200° C., and in certain aspects, optionally or greater than or equal to about 175° C. to less than or equal to about 185° C. The aging process may include heating the cast aluminum component to a temperature of greater than or equal to 120° C. to less than or equal to 250° C., optionally greater than or equal to 130° C. to less than or equal to 200° C., and in certain aspects, optionally or greater than or equal to 175° C. to less than or equal to 185° C.

For example, the cast aluminum component may be heated to a temperature greater than or equal to about 120° C., optionally greater than or equal to about 130° C., optionally greater than or equal to about 140° C., optionally greater than or equal to about 150° C., optionally greater than or equal to about 160° C., optionally greater than or equal to about 170° C., optionally greater than or equal to about 180° C., optionally greater than or equal to about 190° C., optionally greater than or equal to about 200° C., optionally greater than or equal to about 210° C., optionally greater than or equal to about 220° C., optionally greater than or equal to about 230° C., optionally greater than or equal to about 240° C., and in certain aspects, optionally greater than or equal to about 240° C. The cast aluminum component may be heated to a temperature less than or equal to about 250° C., optionally less than or equal to about 240° C., optionally less than or equal to about 230° C., optionally less than or equal to about 220° C., optionally less than or equal to about 210° C., optionally less than or equal to about 200° C., optionally less than or equal to about 190° C., optionally less than or equal to about 180° C., optionally less than or equal to about 170° C., optionally less than or equal to about 160° C., optionally less than or equal to about 150° C. optionally less than or equal to about 140° C., optionally less than or equal to about 130° C., and in certain aspects, optionally less than or equal to about 125° C. The cast aluminum component may be heated to a temperature of about 120° C., optionally about 125° C., optionally about 130° C., optionally about 135° C., optionally about 140° C., optionally about 145° C., optionally about 150° C., optionally about 155° C., optionally about 160° C., optionally about 165° C., optionally about 170° C., optionally about 175° C., optionally about 180° C., optionally about 185° C., optionally about 190° C., optionally about 195° C., optionally about 200° C., optionally about 205° C., optionally about 210° C., optionally about 215° C., optionally about 220° C., optionally about 225° C., optionally about 230° C., optionally about 235° C., optionally about 240° C., optionally about 245° C., and in certain aspects, optionally about 250° C.

Such temperatures may be maintained for a time greater than or equal to about 0.5 hour to less than or equal to about 20 hours, optionally greater than or equal to about 1 hour to less than or equal to about 10 hours, and in certain aspects, optionally greater than or equal to about 4 hours to less than or equal to about 8 hours. Such temperatures may be maintained for a time greater than or equal to 0.5 hour to less than or equal to 20 hours, optionally greater than or equal to 1 hour to less than or equal to 10 hours, and in certain aspects, optionally greater than or equal to 4 hours to less than or equal to 8 hours.

For example, the temperature may be maintained for a time greater than or equal to about 0.5 hour, optionally greater than or equal to about 1.5 hours, optionally greater than or equal to about 2.5 hours, optionally greater than or equal to about 3.5 hours, optionally greater than or equal to about 4.5 hours, optionally greater than or equal to about 5.5 hours, optionally greater than or equal to about 6.5 hours, optionally greater than or equal to about 7.5 hours, optionally greater than or equal to about 8.5 hours, optionally greater than or equal to about 9.5 hours, optionally greater than or equal to about 10.5 hours, optionally greater than or equal to about 11.5 hours, optionally greater than or equal to about 12.5 hours, optionally greater than or equal to about 13.5 hours, optionally greater than or equal to about 14.5 hours, optionally greater than or equal to about 15.5 hours, optionally greater than or equal to about 16.5 hours, optionally greater than or equal to about 17.5 hours, optionally greater than or equal to about 18.5 hours, and in certain aspects, optionally greater than or equal to about 19.5 hours. The temperature may be maintained for a time less than or equal to about 20 hours, optionally less than or equal to about 19.5 hours, optionally less than or equal to about 18.5 hours, optionally less than or equal to about 17.5 hours, optionally less than or equal to about 16.5 hours, optionally less than or equal to about 15.5 hours, optionally less than or equal to about 14.5 hours, optionally less than or equal to about 13.5 hours, optionally less than or equal to about 12.5 hours, optionally less than or equal to about 11.5 hours, optionally less than or equal to about 10.5 hours, optionally less than or equal to about 9.5 hours, optionally less than or equal to about 8.5 hours, optionally less than or equal to about 7.5 hours, optionally less than or equal to about 6.5 hours, optionally less than or equal to about 5.5 hours, optionally less than or equal to about 4.5 hours, optionally less than or equal to about 3.5 hours, optionally less than or equal to about 2.5 hours, optionally less than or equal to about 1.5 hours, and in certain aspects, optionally less than or equal to about 1 hour. The temperature may be maintained for about 0.5 hours, optionally about 1 hour, optionally about 1.5 hours, optionally about 2 hours, optionally about 2.5 hours, optionally about 3 hours, optionally about 3.5 hours, optionally about 4 hours, optionally about 4.5 hours, optionally about 5 hours, optionally about 6 hours, optionally about 7 hours, optionally about 8 hours, optionally about 9 hours, optionally about 10 hours, optionally about 11 hours, optionally about 12 hours, optionally about 13 hours, optionally about 14 hours, optionally about 15 hours, optionally about 16 hours, optionally about 17 hours, optionally about 18 hours, optionally about 19 hours, and in certain aspects, optionally about 20 hours.

Certain features of the current technology are further illustrated in the following non-limiting example.

Example

Example structural castings (i.e., cast aluminum components) may be prepared using gravity casting processes. For example, as illustrated in Table 1 below, a first structural casting may be prepared using a low-iron aluminum alloy that comprises about 0.13 wt. % of iron. A second structural casting may be prepared using a high-iron aluminum alloy that comprises about 0.25 wt. % of iron. Both the low-iron and the high-iron aluminum alloys may include a titanium diboride grain refiner, such that the first and second structural castings have a relatively coarse grain size of about 600 μm. A third structural casting may be prepared in accordance with various aspects of the present disclosure. For example, the third structural casting may include about 60% of post-consumer aluminum scrap, and as such, may have a reduced carbon footprint as compared to the first and second structural castings. The third structural casting may be prepared from an aluminum alloy composition that includes vanadium diboride, a combined concentration of chromium and manganese that is greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. %, and also, a ratio of the combined concentration of manganese and chromium to iron (i.e., (Cr+Mn)/Fe) is greater than or equal to about 0.6 to less than or equal to about 1.2.

TABLE 1 Example Aluminum Alloy Compositions Grain Size Sample Si Mg Cr Mn Fe Ti V Al (um) Example 1 6.9 wt. % 0.31 wt. %   0 wt. %   0 wt. % 0.13 wt. % 0.10 wt. % 0.005 wt. % balance 635 Example 2 7.2 wt. % 0.30 wt. %   0 wt. %   0 wt. % 0.25 wt. % 0.15 wt. % 0.002 wt. % balance 614 Example 3 7.0 wt. % 0.33 wt. % 0.13 wt. % 0.12 wt. % 0.25 wt. % 0.12 wt. %  0.02 wt. % balance 220

Each of the example structural castings were exposed to a heat treatment including a solution heat treatment at about 540° C. for about 6 hours followed by water quenching to about 80° C. and an ageing heat treatment at about 175° C. for about 5 hours. As illustrated in Table 2, the third structural casting exhibits comparable yield strength, ultimate tensile strength, and elongation to fracture as compared to the first structural casting. In addition, the structural casting formed from the third structural casting exhibits significantly higher elongation to fracture than the second structural. The results indicate that low-iron aluminum alloy made from primary or virgin aluminum can be replaced by the high-iron aluminum alloy made using a significant fraction of post-consumer aluminum scrap without sacrificing mechanical properties, by combining the addition of chromium and manganese and effective grain refining processes.

TABLE 2 Tensile Properties of Example Structural Castings Tensile Yield Strength Ultimate Tensile Elongation to Fracture Sample (MPa) Strength (MPa) (%) Example 1 220 285 10.6 Example 2 223 276 6.5 Example 3 225 284 10.3

The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure. 

What is claimed is:
 1. A cast aluminum component prepared using an aluminum alloy composition that comprises: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon; greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium; greater than or equal to about 0.15 wt. % to less than or equal to about 0.8 wt. % of iron; greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese; greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium; and a balance of aluminum, wherein greater than or equal to about 40 wt. % of the aluminum alloy composition is derived from aluminum scrap.
 2. The cast aluminum component of claim 1, wherein the aluminum alloy composition comprises: greater than or equal to about 5 wt. % to less than or equal to about 9 wt. % of silicon; greater than or equal to about 0.25 wt. % to less than or equal to about 0.4 wt. % of magnesium; and greater than or equal to about 0.2 wt. % to less than or equal to about 0.4 wt. % of iron.
 3. The cast aluminum component of claim 1, wherein the aluminum alloy composition comprises: greater than 0 wt. % to less than or equal to about 0.2 wt. % of chromium; and greater than or equal to about 0.1 wt. % to less than or equal to about 0.25 wt. % of manganese.
 4. The cast aluminum component of claim 1, wherein the aluminum alloy composition comprises: greater than or equal to about 6.5 wt. % to less than or equal to about 7.5 wt. % of silicon; greater than or equal to about 0.25 wt. % to less than or equal to about 0.35 wt. % of magnesium; greater than or equal to about 0.2 wt. % to less than or equal to about 0.25 wt. % of iron; greater than 0 wt. % to less than or equal to about 0.15 wt. % of chromium; and greater than or equal to about 0.1 wt. % to less than or equal to about 0.25 wt. % of manganese.
 5. The cast aluminum component of claim 1, wherein a ratio of the combined concentration of chromium and manganese to iron is greater than or equal to about 0.6 to less than or equal to about 1.2, and a ratio of chromium to manganese is less than or equal to about
 2. 6. The cast aluminum component of claim 1, wherein the cast aluminum component has an average grain size less than or equal to about 300 μm at locations where the dendrite arm spacing is greater than or equal to about 30 μm.
 7. The cast aluminum component of claim 1, wherein the cast aluminum component has a tensile yield strength greater than or equal to about 140 MPa to less than or equal to about 270 MPa, and an elongation to fracture greater than or equal to about 7%.
 8. The cast aluminum component of claim 1, wherein the cast aluminum component comprises a grain refiner selected from the group consisting of: vanadium diboride (VB₂), Ti(C,B), and combinations thereof, wherein the grain refiners are embedded within an aluminum grain interior of the cast aluminum component.
 9. The cast aluminum component of claim 1, wherein the aluminum alloy composition consists essentially of: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon; greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium; greater than or equal to about 0.2 wt. % to less than or equal to about 0.8 wt. % of iron; greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese; greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium; and a balance of aluminum.
 10. A method for fabricating a cast aluminum component, the method comprising: forming an aluminum melt using greater than or equal to about 40 wt. % of aluminum scrap; and adjusting the aluminum melt to form an aluminum alloy composition that defines the cast aluminum component, wherein the aluminum alloy composition comprises: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon; greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium; greater than or equal to about 0.15 wt. % to less than or equal to about 0.8 wt. % of iron; greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese; greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium; and a balance of aluminum.
 11. The method of claim 10, wherein the cast aluminum component has an average grain size less than or equal to about 300 μm at locations where the dendrite arm spacing is greater than or equal to about 30 μm.
 12. The method of claim 10, wherein the cast aluminum component comprises a grain refiner selected from the group consisting of: vanadium diboride (VB₂), Ti(C,B), and combinations thereof, wherein the grain refiners are embedded within an aluminum grain interior of the cast aluminum component.
 13. The method of claim 10, wherein the aluminum alloy composition has a ratio of the combined concentration of chromium and manganese to iron is greater than or equal to about 0.6 to less than or equal to about 1.2, and a ratio of chromium to manganese is less than or equal to about
 2. 14. The method of claim 10, wherein the aluminum alloy composition comprises: greater than or equal to about 6.5 wt. % to less than or equal to about 7.5 wt. % of silicon; greater than or equal to about 0.25 wt. % to less than or equal to about 0.35 wt. % of magnesium; greater than or equal to about 0.2 wt. % to less than or equal to about 0.25 wt. % of iron; greater than 0 wt. % to less than or equal to about 0.15 wt. % of chromium; and greater than or equal to about 0.1 wt. % to less than or equal to about 0.25 wt. % of manganese.
 15. The method of claim 10, further comprising: casting the aluminum alloy composition using a casting method selected from the group consisting of: gravity casting, low pressure die casting, semi-solid die casting, and counter pressure casting, and combinations thereof to form a cast aluminum component precursor; heat treating the cast aluminum component precursor, wherein the heat treating comprises: heating the cast aluminum component precursor to a first temperature greater than or equal to about 450° C. to less than or equal to about 550° C. to form a heated cast aluminum component precursor; maintaining the heated cast aluminum component precursor at the first temperature for greater than or equal to about 30 minutes to less than or equal to about 12 hours; and cooling the heated cast aluminum component precursor to a second temperature less than or equal to about 120° C. to form a cooled cast aluminum component precursor; and aging the cooled cast aluminum component precursor to form the cast aluminum component, wherein aging comprises: heating the cooled cast aluminum component precursor to a third temperature greater than or equal to about 120° C. to less than or equal to about 250° C. to form a reheated cast aluminum component precursor; and maintaining the reheated cast aluminum component precursor at the third temperature for a time greater than or equal to about 30 minutes to less than or equal to about 20 hours.
 16. A method for fabricating a cast aluminum component, the method comprising: preparing an aluminum melt that forms the cast aluminum component, wherein the aluminum melt comprises: greater than or equal to about 3 wt. % to less than or equal to about 9 wt. % of silicon; greater than or equal to about 0.2 wt. % to less than or equal to about 0.6 wt. % of magnesium; greater than or equal to about 0.15 wt. % to less than or equal to about 0.8 wt. % of iron; greater than or equal to about 0.15 wt. % to less than or equal to about 0.6 wt. % of a combined concentration of chromium and manganese; greater than or equal to about 0.05 wt. % to less than or equal to about 0.2 wt. % of a combined concentration of vanadium and titanium; and a balance of aluminum.
 17. The method of claim 16, further comprising: casting the aluminum melt to form the cast aluminum component, wherein the cast aluminum component has an average grain size less than or equal to about 300 μm at locations where the dendrite arm spacing is greater than or equal to about 30 μm.
 18. The method of claim 17, further comprising: heat treating the cast aluminum component, wherein the heat treating comprises: heating the cast aluminum component to a first temperature greater than or equal to about 450° C. to less than or equal to about 550° C. to form a heated cast aluminum component; maintaining the heated cast aluminum component at the first temperature for greater than or equal to about 30 minutes to less than or equal to about 12 hours; and cooling the heated cast aluminum component to a second temperature less than or equal to about 120° C.
 19. The method of claim 17, further comprising: aging the cast aluminum component, wherein aging comprises: heating the cast aluminum component to a temperature greater than or equal to about 120° C. to less than or equal to about 250° C.; and maintaining the third temperature for a time greater than or equal to about 30 minutes to less than or equal to about 20 hours.
 20. The method of claim 16, wherein the aluminum melt has a ratio of the combined concentration of chromium and manganese to iron is greater than or equal to about 0.6 to less than or equal to about 1.2, and a ratio of chromium to manganese is less than or equal to about
 2. 